Double-storey extensions across Middlesbrough
Middlesbrough homeowners can use us for the whole double-storey extension project: survey, design, planning or permitted development checks, building regulations and the build itself.
- Guide price in MiddlesbroughFrom £35,500 inc VAT
- PlanningUsually a householder application
- Build time16–24 weeks on site
- Postcode districtsTS1, TS2, TS3, TS4, TS5

Planning rules that apply in Middlesbrough
In England a two-storey rear extension is permitted development only if it projects no more than 3 m from the original rear wall, sits at least 7 m from the rear boundary, matches the roof pitch and uses obscure, non-opening side windows upstairs. Most two-storey extensions therefore go through a householder planning application, which costs £548 from 1 April 2026 and normally takes about 8 weeks.
Before any drawing is finalised we check whether the house is listed, in a conservation area or subject to an Article 4 direction.
Building over or within 3 m of a public sewer needs the water company's consent, usually through a build-over agreement, before the foundations go in.
If the work involves a shared wall, building on the boundary, or digging foundations within 3 m (sometimes 6 m) of a neighbour's building, the Party Wall etc. Act 1996 applies and notice must be served before work starts: two months for work to a party wall, one month for new walls on the boundary and for excavations.
Applications are decided by the local planning authority (your district, borough or unitary council).
What is included
- Building regulations drawings and structural design
- Ground and first floor structure, roof tied into the existing roof
- Householder planning application where needed
- Measured survey, design and planning drawings
The roof is what makes a two-storey extension look right or wrong. We match the pitch and materials of the main house wherever possible and plan the upstairs layout around the existing landing so the new rooms feel original rather than bolted on.
Local to Middlesbrough
Postcode districts we cover around Middlesbrough include TS1, TS2, TS3, TS4, TS5, TS6. Nearby, we also take on projects in Redcar (8 miles), Northallerton (19 miles), Whitby (22 miles), Ripon (32 miles).
Homes across Yorkshire and the Humber range from back-to-back and through terraces to large suburban semis, and extension options vary with them.
What should I budget for a double-storey extension in Middlesbrough?
These guide figures apply our Yorkshire and the Humber adjustment (×0.94) to national rates. They include VAT at 20% and cover the build itself; design and council fees are listed separately.
Typical rates in Middlesbrough: £1,460 to £2,820 per m² including VAT, depending on specification.
| Size | Essential | Standard | Premium |
|---|---|---|---|
| 3 m × 4 m, two floors 24 m² | £35,500 – £43,000 | £40,500 – £53,500 | £51,500 – £68,000 |
| 4 m × 4 m, two floors 32 m² | £46,500 – £56,000 | £54,000 – £71,000 | £69,000 – £90,500 |
| 4 m × 6 m, two floors 48 m² | £69,500 – £83,500 | £81,000 – £106,500 | £103,500 – £135,500 |
For a figure based on your own dimensions, use our guide-price tool.
Our process, step by step
Site visits are free and there is no obligation. Where drawings are needed, the design stage is priced in writing before it starts.
Free site visit
First, a site visit: we look at the house, garden, access and drains and listen to what you need.
Design and approvals
We draw the design, agree it with you and handle planning or permitted development checks and building regulations.
Fixed written price
You receive a written, itemised price and programme. Nothing starts until you are happy with it.
Build and sign-off
Work is carried out to the agreed programme, inspected by building control and signed off at the end.
Double-storey extension questions answered
Will my neighbours in Middlesbrough be involved?
If a planning application or prior approval is needed, the council notifies neighbours. If the work is on or near a shared boundary, party wall notices may also be needed.
Do I need building regulations approval in Middlesbrough?
Yes. Almost every extension needs it, whatever the planning route. We prepare the drawings and book the inspections.
How long does a double-storey extension take to build in Middlesbrough?
On site, typically 16 to 24 weeks once approvals are in place. Before that, allow 8–16 weeks design and approvals.
Is a two-storey extension cheaper per square metre?
Usually. Our guide range is about £1,460 to £2,820 per m² of new floor area including VAT, compared with £1,640 to £3,200 per m² for single-storey work, because the foundations and roof are shared across two floors.
Do I need a Party Wall Agreement?
If you are in England or Wales and the work involves a shared wall or digging foundations close to a neighbour, the Party Wall etc. Act 1996 applies and notices must be served before work starts. We tell you which notices are needed.
Book a free site visit in Middlesbrough
We will measure up, check the planning position and give you honest guide figures.
- Free, no-obligation site visit
- Planning route checked before you spend on drawings
- Written price once the design is agreed
- Building control sign-off at the end
Prefer to talk? Call 0800 088 6341 or .
Book a free site visit
Tell us a little about the project and we will arrange a time.